What device is used to convert one type of electrical signal into another?

The media converter is the device specifically designed to convert one type of electrical signal into another. It is commonly used in networking to facilitate communication between different types of media, such as copper and fiber optic cables. For example, a media converter can take an Ethernet signal from a standard twisted pair cable and convert it into a light signal for transmission over fiber optic cable. This function is crucial in modern networks where different segments may utilize varying physical media types, ensuring seamless connectivity.

Other devices like hubs, routers, and repeaters have different primary functions. Hubs are used to connect multiple Ethernet devices, creating a single network segment but do not alter the type of signal. Routers direct data packets between different networks and can perform some signal conversion related to protocol, but their main role is routing, not direct signal conversion. Repeaters regenerate and amplify signals to extend transmission distance over the same type of medium, but they do not change the type of electrical signal; they simply strengthen it to maintain integrity over longer distances.